JPH05271930A - Coating method and coating device for spherical body - Google Patents

Abstract

PURPOSE:To coat the entire periphery of spherical bodies with uniform films and to improve the surface characteristics and functions of the spherical bodies by supplying evaporated film forming materials while turning the spherical bodies placed on the recesses of a tray by the vibration of this tray. CONSTITUTION:The film forming materials are evaporated and supplied from an evaporating means 15 to the spherical bodies 9 supported by a spherical body supporting mechanism 4 within a chamber 1 connected to a discharge port 3. A bias voltage is impressed from a cable 12 to the spherical bodies and a working gas is introduced from a gas introducing port 3. This spherical body supporting mechanism 4 is constituted by extending the tray 7 on a conductive supporting base 5 fixed to the bottom plate of the chamber 1 via a cushion material 6. This tray 7 consists of a material which is softer than the spherical bodies and is conductive. The tray is formed with the recessed parts 8 of about 2 to 3 times the diameter of the spherical bodies 9. The spherical bodies 9 are placed in these recessed parts 8 and are finely vibrated at several thousand times/min by a vibrator 10. As a result, the spherical bodies 9 are turned within the recessed parts 8 and the film forming materials are uniformly deposited on the entire periphery thereof. The surfaces are thus coated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to spheres and rollers used in rolling bearings for various machines, small diameter balls for ballpoint pens,
Other spherical or roller-shaped products (in this specification,
Objects that are circular when viewed from either side are called spheres.)
The present invention relates to a method for coating a film on the surface of the substrate for the purpose of imparting wear resistance, seizure resistance, lubricity, corrosion resistance and the like, and an apparatus therefor.

[0002]

2. Description of the Related Art As a method for coating the surface of a sphere, the sphere is placed in a mesh rotating drum,
By rotating the drum, the spheres are stirred and rolled inside the drum, while the coating material is vaporized by vaporizing means arranged outside the drum, for example, a sputtering device or an ion plating device, and then vaporized. There is a method of depositing and coating a coating material on the surface of a rolling sphere in the drum.

[0003]

SUMMARY OF THE INVENTION In this conventional method,
When the spheres roll in the drum, the spheres may violently collide with each other, or the spheres may violently collide with or rub against the drum, so that a part of the coating film just attached to the surface of the sphere may peel off. And such a coating redeposits on the surface of the sphere during the course of the coating process.
Then, the redeposited film acts as a masking material in the process of coating, and grows a columnar porous film with many gaps around it. Such a coating has a low density and a low adhesiveness, and there is a problem that the above-mentioned surface characteristics and functions are inferior. Further, there is a problem that the redeposited coating film easily comes off and causes a pit-like film defect.

The present invention has been made to solve the above-mentioned problems (technical problems) of the prior art. When coating the surface of a sphere, the sphere can be smoothly rotated without giving an impact to the sphere. An object of the present invention is to provide a coating method and a coating apparatus for a sphere that can be moved and can be coated with a uniform coating on the entire circumference of the sphere.

[0005]

In order to achieve the above object, a method for coating a sphere according to the present invention is such that the vaporized film substance is deposited on the surface of the sphere while rotating the sphere, In the coating method, the sphere is rotated by placing the sphere on a tray and vibrating the tray to rotate the sphere.

[0006]

[Operation] The sphere is rotated by the vibration of the tray. In the process of continuing the rotation of the sphere, the vaporized coating material is deposited on the surface of the sphere to form a coating.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1 showing the coating apparatus, reference numeral 1 is a coating chamber, which is constituted by a metallic vacuum chamber and is grounded as shown in the drawing. 2 is an exhaust port in the chamber, which is connected to a vacuum pump.
Reference numeral 3 is a gas introduction port for introducing a working gas for coating, for example, argon, or a reactive gas for forming a film. Next, 4 shows a support mechanism for a spherical body provided in the chamber 1. Reference numeral 5 denotes a support base in the mechanism, which is made of a conductive material and is attached to the bottom plate of the chamber 1 via a cushion material 6 for absorbing vibration. The cushion material 6 also serves as electrical insulation between the support 5 and the chamber 1. Reference numeral 7 denotes a tray mounted on the support base 5, which has rigidity enough to withstand vibration as will be described later, and is softer than the sphere so as not to damage the sphere to be placed on the tray, and has conductivity. Is formed of a material having A stainless material (for example, SUS304) is used as an example of the material. Denoted at 8 is a recess formed on the upper surface of the tray 7, which is used to individually store the spheres.
Are formed side by side on the upper surface of. The planar size of the recess 8 is set to 2-3 times the diameter of the sphere. The recesses 8 are formed by embossing, for example. 9
Indicates a sphere individually placed in each of the recesses 8. Reference numeral 10 denotes a vibrator attached to the support base 5, which vibrates the tray 7 via the support base 5. The vibrator 10 is designed to generate vibrations of extremely fine amplitude thousands of times per minute. As the vibrator 10, for example, a known electromagnetic vibrator is used. 11 is a protective cover that is integrally formed with the tray 7, and the vibrator 10
To protect the film from being coated on it.
Reference numeral 12 is a cable connected to the support base 5 for applying a bias to the sphere 9 via the support base 5 and the tray 7, and is connected to a well-known bias / etching power source (not shown). Next, reference numeral 15 denotes a sputtering device shown as an example of a vaporization means, which is of a magnetron type and is attached to the ceiling portion of the chamber 1 so as to face the tray 7 as shown in the drawing. Reference numeral 16 is a cathode in the sputtering apparatus, 17 is a target material attached to the cathode 16, and 18 is a permanent magnet having a polarity as shown. Reference numerals 19 and 20 indicate the inlet and outlet of cooling water, respectively. Reference numeral 21 is an insulator for insulating the cathode 16 from the chamber 1, and 22 is a dark space shield. 23 is a power source for sputtering.

Next, the coating operation on the sphere 9 by the coating apparatus will be described. First, the spheres 9 are placed on the multiple recesses 8 of the tray 7, respectively. Next, the tray 7 in that state is set on the support base 5 in the chamber 1 as illustrated. After that, the chamber 1 is evacuated and the working gas is introduced into the chamber 1 through the gas inlet 3. In this state, the sputtering power supply 23 is energized to the sputtering device 15, the bias is applied to the sphere 9 from the bias power supply, and the vibrator 10 is operated. When the vibrator 10 is operated as described above, its vibration is transmitted to the tray 7 via the support base 5,
The tray 7 vibrates minutely. This vibration causes sphere 9
Rotates while being positioned in the concave portion 8 and always performs a random rotary motion. On the other hand, when the sputtering device 15 is energized, the target material 17 is sputtered and the coating material is vaporized. The vaporized coating material is deposited on the surface of the sphere 9 which is biased. In this case, since the sphere 9 is rotating, the coating material is uniformly deposited on the entire circumference thereof, and a coating having a uniform thickness is formed on the entire circumference of the sphere 9. When the coating film is continuously produced for a predetermined time and the thickness of the coating film attached to the surface of the spherical body 9 reaches a predetermined thickness, the sputtering device 15 is energized, a bias is applied to the spherical body 9, and the tray 7 is vibrated. Is stopped, and the inside of the chamber 1 is returned to normal pressure to take out the spherical body 9 after the coating process.

As the target material 17, a material corresponding to a coating material to be coated on the sphere 9, such as gold, silver or molybdenum disulfide, is used. When the coating substance to be coated is titanium carbide, titanium nitride, or the like, titanium is used as the target material 17, and the gas introduced into the chamber 1 is a reactive gas such as acetylene or nitrogen.

Next, as the vaporizing means used in the coating apparatus, an arc ion plating apparatus using a cathode arc evaporation source is used in place of the sputtering apparatus so that the cathode in the apparatus faces the tray 7. It may be installed above the chamber 1. Further, as another example of the vaporization means, plasma CV is used.
A D device or a plasma polymerization device may be used. When these plasma CVD apparatuses or plasma polymerization apparatuses are used, the plasma circulates to various places in the chamber 1. Therefore, the trays 7 have a multi-tiered stacking structure and each sphere is placed on each tray to coat the spheres. Processing may be performed. As a method of forming the recess in the tray, the recess may be formed by a method of fixing the ring material to a flat tray in addition to embossing.

[0011]

As described above, in the present invention, when the surface of the sphere 9 is coated, the coating substance is deposited on the surface of the sphere 9 while rotating the sphere 9, so that the entire circumference can be coated with the coating. Of course,

The rotation of the sphere 9 for coating as described above is performed by vibrating the tray 7
Since it rotates, the sphere has the feature that it can be rotated so that it slides in a state where it spins like a spin. This means that during the coating, the sphere can be rotated without giving an impact such as peeling off a part of the coating just formed on the surface of the sphere, and at any part of the entire circumference of the sphere. Also, there is a usefulness that a film can be formed without interruption, a uniform film can be coated on the entire circumference, and a high-quality product having excellent surface characteristics and functions without defects can be produced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a coating apparatus.

[Explanation of symbols]

 1 chamber 7 tray 9 sphere 10 vibrator 15 vaporization means

Claims (2)

[Claims] 1. A method of coating the surface by depositing a vaporized coating substance on the surface of a sphere while rotating the sphere, wherein the sphere is rotated by placing the sphere on a tray. A method for coating a sphere, wherein the sphere is rotated by vibrating the tray. 2. A coating method for a sphere, comprising a support means for supporting the sphere and a vaporizing means for vaporizing a coating substance for coating the surface of the sphere in a coating chamber. In the apparatus, the supporting means is a tray on which the sphere can be placed, and the tray is provided with a vibrator for applying a vibration for rotating the sphere to the tray. Sphere coating equipment.